NASA's Hubble Space Telescope has captured the best ever view of stellar debris disk warped by a massive exoplanet.
Astronomers took the most detailed edge on picture to date of a large disk of gas and dust encircling the 20 million-year-old star Beta Pictoris.
Beta Pictoris was the only star to date where astronomers have detected an embedded giant planet in a directly-imaged debris disk. The planet, which was discovered in 2009, goes around the star once every 18 to 20 years. This allowed scientists to study in a comparably short time how a large planet distorts the massive gas and dust encircling the star. These observations should yield new insights into how planets are born around young stars.
The new visible-light Hubble image traces the disk to within about 650 million miles of the star. The giant planet orbits at 900 million miles, and was directly imaged in infrared light by the European Southern Observatory's Very Large Telescope six years ago.
When comparing the latest 2012 images to Hubble images taken in 1997, astronomers find that the disk's dust distribution has barely changed over 15 years despite the fact that the entire structure was orbiting the star like a carousel. This means the disk's structure was smooth and continuous, at least over the interval between the Hubble observations.
The disk was easily seen because of its edge-on angle, and is especially bright due to a very large amount of starlight-scattering dust. What's more, Beta Pictoris was 63 light-years away, closer to Earth than most of the other known disk systems.
Though nearly all of the approximately two-dozen known light-scattering circumstellar disks have been viewed by Hubble to date, Beta Pictoris was the first and best example of what a young planetary system looks like.
For one thing, the Beta Pictoris disk is exceptionally dusty. This might be due to recent major collisions among unseen planet and asteroid-sized objects embedded within the disk. In particular, a bright lobe of dust and gas on the southwestern side of the disk might be the result of the pulverisation of a Mars-sized object in a giant collision.
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